Ethereum co-founder Vitalik Buterin recently recommended using privacy-oriented Zcash’s zk-SNARKs technology in order to help scale the Ethereum blockchain to process 500 transactions per second (TPS).

zk-SNARK is short for “Zero-Knowledge Succinct Non-Interactive Argument of Knowledge” and is a type of “proof construction” that allows an entity to prove that they’re in “possession of certain information … without revealing that information, and without any interaction between the prover and verifier.”

Zero-Knowledge Proofs

In other words, zk-SNARK is derived from zero-knowledge cryptography and it “potentially gives you the ability… to prove something about a data structure without revealing the data inside the data structure”, according to Peter Van Valkenburgh, the director of research at Coin Center (a non-profit focused on researching policies related to cryptocurrencies).

Buterin noted in his EthResearch blog post (on September 22nd) that transaction relayers on the Ethereum blockchain could potentially process transactions in bulk by batching, or bundling, them together and then using zk-SNARK to “mass-validate” them.

Buterin's explaination reads in part:

There are two classes of user: (i) transactor, and (ii) relayer. A relayer takes a set of operations from transactors, and combines them all into a transaction and makes a ZK-SNARK to prove the validity, and publishes the ZK-SNARK and the transaction data in a highly compressed form to the blockchain. A relayer gets rewarded for this by transaction fees from transactors.

Vitalik Buterin

Per the Russian-Canadian programmer, this approach could greatly compress data and allow validators to process all transactions “on-chain” (on the main Ethereum blockchain) - without having to rely on sidechains or second-layer channels.

Scaling To 500 TPS

Integrating zk-SNARK technology on the Ethereum network could potentially enable it to process up to 500 TPS, Buterin estimated. At present, the Ethereum blockchain can only handle an average of 15 TPS, so this would significantly improve its network capacity.

Ethereum’s developers have been working on several second-layer solutions and other performance-enhancing upgrades. As covered on CryptoGlobe, Ethereum’s Constantinople (hard fork) upgrade, which includes five different ethereum improvement proposals (EIP), is tentatively scheduled for next month.

Constantinople is aimed at improving Ethereum’s network efficiency while also reducing mining rewards from 3 ETH to 2 ETH per block. Many ETH miners have complained about the decrease in mining rewards and have considered switching to mining other digital currencies.

Effectively scaling the Ethereum blockchain is crucial as it has become too congested due to the large number of decentralized applications (DApps) that have been deployed on its platform.